Compositions containing cationic nitrogenous compounds in the form of quaternary ammonium salts and substituted imidazolinium salts having two long chain acyclic aliphatic hydrocarbon groups are commonly used to provide fabric softening benefits when used in laundry rinse operations (See, for example, U.S. Pat. Nos. 3,644,203, Lamberti et al., issued Feb. 22, 1972; and U.S. Pat. No. 4,426,299, Verbruggen, issued Jan. 17, 1984; also "Cationic Surface Active Agents as Fabric Softeners," R. R. Egan, Journal of the American Oil Chemists' Society, January 1978, pages 118-121; and "How to Choose Cationics for Fabric Softeners," J. A. Ackerman, Journal of the American Oil Chemists' Society, June 1983, pages 1166-1169).
Quaternary ammonium salts having only one long chain acyclic aliphatic hydrocarbon group (such as monostearyltrimethyl ammonium chloride) are less commonly used because for the same chain length, compounds with two long alkyl chains were found to provide better softening performance than those having one long alkyl chain. (See, for example, "Cationic Fabric Softeners," W. P. Evans, Industry and Chemistry, July 1969, pages 893-903). U.S. Pat. No. 4,464,272, Parslow et al., issued Aug. 7, 1984, also teaches that monoalkyl quaternary ammonium compounds are less effective softeners.
Another class of nitrogenous materials that are sometimes used in fabric softening compositions are the nonquaternary amide-amines. A commonly cited material is the reaction product of higher fatty acids with hydroxy alkyl alkylene diamines. An example of these materials is the reaction product of higher fatty acids and hydroxyethylethylenediamine (See "Condensation Products from .beta.-Hydroxyethylethylenediamine and Fatty Acids or Their Alkyl Esters and Their Application as Textile Softeners in Washing Agents," H. W. Eckert, Fette-Seifen-Anstrichmittel, September 1972, pages 527-533). These materials are usually cited generically along with other cationic quaternary ammonium salts and imidazolinium salts as softening actives in fabric softening compositions. (See U.S. Pat. Nos. 4,460,485, Rapisarda et al., issued July 17, 1984; U.S. Pat. No. 4,421,792, Rudy et al., issued Dec. 20, 1983; U.S. Pat. No. 4,327,133, Rudy et al., issued Apr. 27, 1982). U.S. Pat. No. 3,775,316, Berg et al., issued Nov. 27, 1973, discloses a softening finishing composition for washed laundry containing (a) the condensation product of hydroxyalkyl alkylpolyamine and fatty acids and (b) a quaternary ammonium compound mixture of (i) from 0% to 100% of quaternary ammonium salts having two long chain alkyl groups and (ii) from 100% to 0% of a germicidal quaternary ammonium compound of the formula [R.sub.5 R.sub.6 R.sub.7 R.sub.8 N].sup.+ A.sup.- wherein R.sub.5 is a long chain alkyl group, R.sub.6 is a member selected from the group consisting of arylalkyl group and C.sub.3 -C.sub.18 alkenyl and alkadienyl containing one or two C.dbd.C double bonds, R.sub.7 and R.sub.8 are C.sub.1 -C.sub.7 alkyl groups, and A is an anion. U.S. Pat. No. 3,904,533, Neiditch et al., issued Sept. 9, 1975, teaches a fabric conditioning formulation containing a fabric softening compound and a low temperature stabilizing agent which is a quaternary ammonium salt containing one to three short chain C.sub.10 -Chd 14 alkyl groups; the fabric softening compound is selected from a group consisting of quaternary ammonium salts containing two or more long chain alkyl groups, the reaction product of fatty acids and hydroxyalkyl alkylene diamine, and other cationic materials.
It has been found that the common cationic fabric softeners can lose much of their effectiveness in the rinse bath by virtue of the carryover of detergent components from the wash cycle. The detrimental effect of anionic surfactants on cationic fabric softeners was discussed in U.S. Pat. No. 3,974,076, Wiersema et al., issued Aug. 10, 1976.
It has now been found that nonionic detergents also may have detrimental effect on the cationic fabric softeners, sometimes even more so than the anionic surfactants. The problem of interference by carryover detergents may be overcome by very thoroughly rinsing the fabrics. However, since the average user is not disposed to take such extreme measures, it is advantageous to have fabric softening compositions which perform well across major categories of detergents. Current representatives of major detergent categories are TIDE.sup.R (anionic detergents), WISK.sup.R (anionic detergents rich in LAS (linear alkylate sulfonate) surfactant) and CONCENTRATED ALL.sup.R (nonionic detergents).